Bump MediatR from 8.0.1 to 8.1.0 (#303)

Bumps [MediatR](https://github.com/jbogard/MediatR) from 8.0.1 to 8.1.0.
- [Release notes](https://github.com/jbogard/MediatR/releases)
- [Commits](LuckyPennySoftware/MediatR@v8.0.1...v8.1.0)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Build.targets

@@ -36,7 +36,7 @@
         <PackageReference Update="System.Reactive" Version="4.4.1" />
         <PackageReference Update="System.Collections.Immutable" Version="1.7.1" />
         <PackageReference Update="Microsoft.Reactive.Testing" Version="4.4.1" />
-        <PackageReference Update="MediatR" Version="8.0.1" />
+        <PackageReference Update="MediatR" Version="8.1.0" />
         <PackageReference Update="MediatR.Extensions.Microsoft.DependencyInjection" Version="8.0.0" />
         <PackageReference Update="Bogus" Version="30.0.2" />
         <PackageReference Update="Snapper" Version="2.2.4" />